LITTLE ROCK (AP) — An Arkansas judge on Friday continued a stay of his ruling against the state's new voter ID law, but appeared to leave open the possibility that he could reconsider and block the law's enforcement during next month's primary.

The secretary of state, meanwhile, told the judge he planned to appeal the ruling to the state Supreme Court.

Pulaski County Circuit Judge Tim Fox formally entered his ruling that requiring voters to show photo identification before casting a ballot is unconstitutional. The five-page order formalizes a ruling Fox issued from the bench on May 2, when Fox issued a preliminary injunction against the law but said he wouldn't block its enforcement during Tuesday's primary.

Fox's written order keeps the stay in place, pending a state Supreme Court decision in a separate case where Fox had ruled the law unconstitutional. The state Supreme Court last week vacated Fox's ruling in that decision, saying he didn't have the authority to strike down the law in that case since it had focused on absentee ballots and not the law's constitutionality. The judge encouraged attorneys to file a formal request if they want him to modify his Friday decision.

The American Civil Liberties Union of Arkansas and the Arkansas Public Law Center had sued the state over the law on behalf of four voters who the groups said would be harmed by the new requirement. Jeff Priebe, an attorney for the groups, said Fox's decision leaves open the possibility that he could lift his stay. Priebe said he's talking with the plaintiffs about the next step.

"If the defendants choose to appeal, we look forward to presenting this to the Arkansas Supreme Court to ensure that all Arkansans who are qualified can vote," he said.

Tuesday's primary was the first statewide enforcement of the voter ID law, which was approved by the Republican-led Legislature last year. The primary runoff will be held June 10, with the Republican runoff for attorney general as the only statewide race.

A spokeswoman for Secretary of State Mark Martin, who was named as a defendant in the lawsuit, declined to comment and said Martin's office is reviewing the decision. Martin filed a notice of appeal with Fox later Friday.

A spokeswoman for Attorney General Dustin McDaniel said he also planned to appeal Fox's ruling.